The actress and author of "The Kind Diet" confessed that sometimes she slips up -- and dairy is her downfall.

"If I was at a party and there was a tray of cheese sitting there and I had had drinks, then I might have a bite," Silverstone told UsMagazine.com at an EcoTools event in New York on Wednesday.

Silverstone doesn't let her momentary lapse get to her, though. "It's human," she said. "It's a really good reminder that sometimes you need to have what you remember is this good thing. Because then you have it, and you're like, 'Actually that wasn't better than the recipes in my book,'" Silverstone told Us.

"Being flexible that way makes more people comfortable," she said. "If I'm rigid about it and I'm perfect, then no one is going to be able to be like me because I'll be this icy, rigid thing."

Silverstone credits the vegan diet with better health. "I haven't been to a doctor in 13 years," she told Us. "I don't have to worry about calories. I don't have to worry about how I look because I know that what I do makes me look my best."